How do small woofers produce large bass?
Hi All,
I am looking at loudspeakers... I currently own the Arendal 1723 THX Monitors. 2 8" woofers each. I listen to probably 80% home theater and 20% pure two-channel music of all sorts. I am contemplating upgrading the speakers, and there are a number that I am very interested in. The Arendals are killer for music and home theater. In fact crazy amazing at home theater. I have also 2 SVS SB-3000 subs.
But as we all know, wanting to upgrade. blah blah ad nauseum. :)
And most everything I’m looking at has 6.5" bass drivers, usually 2 per speaker. I am looking at the Acoustic Energy Corinium, the KEF R11 Meta, the Dali Opticon 8 MKII, and the PSB T600.
I have a fear that the bass will be plenty for two-channel music, but won’t have that bad-ass slam of the Arendal’s dual 8" drivers. So my question is sort of a scientific one or a physics one. I am baffled as to how the 6.5" drivers in all of these new speakers are going to produce home theater sized bass. I’ve watched every video, read every article about those 4 contenders (above) - and everything/everybody says essentially "no worries, the woofers are lighter and faster, and since there are two of them, they make a great deal of bass. I just think I’m not seeing the "science" or "physics" of that. Like how are these 6.5" drivers going to handle something incredibly powerful/dynamic (bomb blasts/gun shots/thunder/explosions etc etc??? I’m afraid I’ll be let down by something like the PSB T600’s or the KEF R11 Metas when head to head with the dual 8" drivers in my Arendals. I’m hoping people can assure me and/or run through the science.... thanks to all. Oh, and yes, I do cross over to my two subs at 60Hz.
The only way a smaller driver keeps up with a larger one when producing low bass is to increase it's excursion--plain and simple However, there is always a price to pay. Higher excursion demands much more power from your amp AND there is a limit to excursion AND the more the excursion the more the distortion. The mid bass impact issue is much more complicated as other factors enter into that equation. In the end you will need an audition in your own system. |
Generally speaking, the farther a woofer needs to move to produce the desired amount of deep bass output, the greater distortion both from the amp and the driver’s components w/ all other things being equal. This was a basic tenet of Paul Klipsch. Thus, larger woofers with higher sensitivity in bigger cabinets have an inherent advantage of producing deep bass at higher output levels but at the cost of other issues like cabinet size & quality requirements & potential effects on imaging & unwanted reflections from the midrange & tweeters. |
Not without high distortion and strain, (excursion = distortion) see here bass myths.😎 Mike |
The comments about moving air and needing more excursion from a smaller woofer are correct. And excursion almost always leads to higher distortion. That makes the new Purifi drivers very interesting. They have long excursion and maintain low distortion due to new design characteristics. But they are expensive and not many speakers use them yet. But it's worth looking for speakers using them. The Radiant Acoustics Clarity 6.2 is slightly bigger than an LS3/5a with a 6.5" woofer and it goes down to 35 HZ. A speaker with 2 of these woofers would probably do what you want. |
